No audio from speakers on some laptops using audiohd
On some laptops, the amplifier(s) for the speakers are apparently not getting powered up. The headphone jacks work OK, but you can hear at most a very faint sound from the built-in speakers.
Here are a couple laptops known to suffer from this:
Dell Precision M4500
Lenovo ThinkPad X201
Updated by Gordon Ross about 8 years ago
- File audiohd-356468a83aa7a98d5148684266ebeb19c97e21cc.patch audiohd-356468a83aa7a98d5148684266ebeb19c97e21cc.patch added
I ran across a fix for this (attached) that was posted by Vladimir Kirillov about two years ago.
[ pasted here ]
My Thinkpad X201 has a Conexant CX20585 codec with audiohd.
After boot the speaker works fine but stops after I plug/unplug the headphones.
Digging into the code/spec helped me discover that setting
AUDIOHDC_PIN_CONTROL_HP_ENABLE bit on the speaker pin
(which means 'enable a low impendance amplifier associated with the
output' according to the spec makes the speaker remain silent).
I'm not sure this is valid for all cases/codecs, so please test
and/or provide your feedback.
Commit in my own github tree: